Painting and Birding 'round the Long Island Sound

Though I am primarily a 2-d artist, my "day-job" as an exhibit preparator at a museum frequently calls for me to work "outside the box".  The latest science exhibit at the Bruce Museum in Greenwich, CT  is called "Last Days of Pangea", and tells the story of the cataclysmic environmental changes that occurred between the Triassic and Jurassic periods, about 200 million years ago, and the impact that had on the evolution of life.  As it happens, our area, in the northeastern United States, is known for its preservation of fossils from this transition, though the fossils are usually small, and the larger animals best known by footprints only.  It was decided that, to add interest, I would be tasked with creating restorations of several extinct critters.  Rather than paintings or drawings, however, I would create 3- dimensional models, giving this exhibit a new and interesting twist.

The animals of the early Jurassic are best represented in our area by footprints.  

Here is a case of them in "Last Days of Pangea" - interesting, but rather dry.

Like many kids, I was fascinated by dinosaurs as a child, and my earliest drawings often featured them.  I retained that interest into adulthood, and as I learned more, I became interested in far more than just dinosaurs.  Dinosaurs are in fact just one chapter in the long and dramatic story of life on this planet- there were many equally interesting animals that lived before, after, and during the age of dinosaurs.  The subject of this latest Bruce Museum show was therefore quite exciting to me, as it focuses on a particularly interesting and underappreciated moment in the evolution of life- a time when dinosaurs were just one small part of a diverse ecosystem full of strange experimental variations along the reptile line, that were then "put to the test" by stressful environmental changes.  In the extinctions that ultimately followed, dinosaurs survived, found themselves relatively unchallenged, and quickly diversified, becoming the dominant terrestrial animals of their time.  The exhibit therefore features many of these odd animals, and it was my job to breathe life into them.

Model of Hypsognathus fenneri, a small, wide-bodied reptile who may have lived

in burrows.

Another interesting aspect to this time period is that much of the action was centered around the local area.  The cataclysmic changes that caused the massive extinctions stemmed from the breakup of the supercontinent "Pangea"- which encompassed all of our planets current continents in one landmass.  As the supercontinent divided along a spreading faultline that would become the Atlantic Ocean, parallel fractures created rift valleys up and down the East Coast of North America.  The lakes that formed in those rift valleys- including one right over Connecticut- preserved the fossils showcased in this exhibit, which not only include bones, but also footprints of animals that wandered the ancient muddy shorelines.

A model of Diplurus, an extinct lungfish related to the modern Coelocanth, whose

fossils can be found in late Triassic sediments in Connecticut.

To begin reconstructing these extinct animals, one must begin with the fossilized bones, which are often incomplete and difficult to interpret.  Our Science Curator, Dr. Daniel Ksepka, was very helpful in getting me all the references I needed, especially the various scientific papers which described these fossils. 

Fossil carapace of Stegomus, and skeletal reconstruction of Stagonolepis, a close relative.

Once we figured out the basic size and general shape of the animal, I began a rough armature.  Typically I would carve one piece of wood for the body, another for the skull, using wire for the neck and tail as well as the limbs.  In a few cases I used plexiglas for thin, transluscent parts such as the flight membranes on Icarosaurus or the fins of fish.  Plexiglass can be carved but also heated into bends and curves that remain rigid once cooled.  Then I began adding two-part sculpting epoxy to fill out the musculature and surface texture, which was based on modern animals of similar form or lifestyle.

Stages in the sculpting of Stegomus, from wood-and-wire armature, to building mass and texture, and finally, painted color patterns.

I also referenced modern animals with a similar lifestyle to guide the colors and patterns when painting the models.  This is an enjoyable stage, when I can free myself a bit and speculate.  Some of the models were placed into mini habitats.  There was not time to create complete dioramas, but I did want to suggest something of the animals presumed habitat. I created simple plants such as horsetails and broad-leaved ferns known from fossils from that time.

The finished model of a juvenile Stegomus arcuatus, among horsetails.  Adults reached about 5 feet in length.

In the case of the glider Icarosaurus and the swimmers Taneytrachelos and Hyperonector, these habitats also served to mount these animals, which were held up by rods hidden in their tails or behind the body.

Icarosaurus, a gliding reptile, and Hyperonector, a presumed swimmer, both from New Jersey.

The show also includes a cast of Postosuchus, a top predator of the time.  These cast bones came to us in pieces, so it was fun figuring out how to put them together.  Fossils of Postosuchus are known from late Triassic rocks in New Mexico, though footprints of animals like them reveal that they also roamed locally.  These were not dinosaurs, but early dinosaurs such as Coelophysis lived alongside them, as well as other unusual reptiles such as the large armored swimmer Vancleavea shown below. 

A cast of the preserved skull and osteoderms of Vancleavea (left), and the resulting model, unpainted and painted.

What an unusual world it must have been, with so many bizarre animals competing with each other!  It took the environmental stresses that started the Jurassic period, which wiped out animals such as Postosuchus and Vancleavea, that allowed the early dinosaurs to diversify and ultimately dominate terrestrial faunas worldwide.

"Last Days of Pangea: in the footsteps of Dinosaurs" can be seen at the Bruce Museum, 1 Museum Drive, Greenwich, now until next summer.